1. Field
This disclosure relates to the management of electric vehicle charging stations queues.
2. Description of the Related Art
The owners of plug-in electric and hybrid electric vehicles, which will be referred to herein as PEVs, typically have a dedicated charging station at the home or other location where the vehicle is normally garaged. However, without the existence of an infrastructure of public charging station, the applications for PEVs will be limited to commuting and other short-distance travel. In this patent, a charging station is considered “public” if it is accessible and usable by plurality of drivers, as opposed to a private charging station located at a PEV owner's home. A “public” charging station is not necessarily accessible to any and all PEVs. Public charging stations may be disposed, for example at commercial buildings, shopping malls, multi-unit dwellings, governmental facilities and other locations.
In the U.S., charging stations usually comply with the Society of Automotive Engineers (SAE) standard, SAE J1772™. This standard refers to charging stations as “electric vehicle support equipment”, leading to the widely used acronym EVSE. However, since the only support actually provided by an EVSE is charging, this patent will use the term electrical vehicle charging station or EVCS.
Typically, EVCS are first-come, first-served. That is, the first user that arrives at an EVCS may use the station and continue to use the EVCS until that user decides to leave. This rewards early arrivals at locations and is typical for normal parking spaces. However, this results in a sub-optimal allocation of the few EVCS typically available in most locations.
For example, a user can leave his or her home fully-charged and arrive at a destination with nearly-full batteries. The user may then park at an EVCS and begin charging his or her electric vehicle. The electric vehicle is fully charged within one to three hours, but the user's car may remain in the spot for the remainder of the day. Meanwhile, other individuals with electric vehicles who arrived later or with lower battery charge levels are unable to access the EVCS.
Throughout this description, elements appearing in figures are assigned three-digit reference designators, where the most significant digit is the figure number where the element is introduced and the two least significant digits are specific to the element. An element that is not described in conjunction with a figure may be presumed to have the same characteristics and function as a previously-described element having the same reference designator.